Paint stirrer



Nov. 17, E953 w. c. GRAY PAINT STIRRER Filed May 7. 1951 26 l2 2O 4 a; l

INVENTOR.

WILLIAM C. GRAY Patented Nov. 17, 1953 UNITED STATES ATENT OFFICE PAINT STIRRER William C. Gray, Detroit, Mich., assignor to The Detroit Edison Company, Detroit, Mich., a corporation of New York Application May 7, 1951, Serial No. 225,028

1 Claim. l The present invention relates to a paint stirrer. t is an object of the present invention to provide a paint stirrer in the form of a tool suitable for use with a driver for effectively stirring and mixing paint.

It is a further object of the present invention to provide a paint stirrer comprising a shaft having inclined paddles or blades at its lower end.

it is a further object of the present invention to provide a paint stirrer comprising a shaft having paddles at its lower end, including a helical rib formation on the shaft of a hand opposite to the direction of intended rotation of the shaft, the rib formation preferably being provided by twisting a shaft of polygonal cross-section,

It is a further object of the present invention to provide a paint stirrer comprisingr a shaft, blades at the lower end of the shaft, said blades being provided by a dat strip of material secured at its center to the end of the shaft, the blade portions being inclined outwardly away from the shaft and also twisted.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, wherein:

Figure 1 is an elevational view, partly in section, showing the 'paint stirrer attached to a power drive unit and in use in a can of paint.

Figure 2 is an enlarged elevational view of the paint stirrer.

Figure 3 is a fragmentary side elevation of the lower end of the paint stirrer shown in Figure 2.

Figure 4 is a section on the line i-l, Figure 2.

Figure 5 is an end view of a blade looking in the direction of the arrow 5, Figure 2.

Figure 6 is a top plan view of the blade portion seen in Figure 5.

Figure '7 is a bottom plan view of the blade portion seen in Figure 5.

As best seen in Figure 1, the invention comprises a paint stirrer indicated generally at lil, which is designed for use with means for rotating the same. In Figure 1 an electric motor l2 is illustrated having a socket l 4 for the reception of the upper end of the paint stirrer, the motor being provided with a handle i6. Any suitable means may be provided for rotating the paint stirrer, An electric drill provided with a conventional chuck for releasably holding the stirrer is useful.

The paint stirrer comprises an elongated shaft i3 and a pair of outwardly extending blades 2t. The shaft I8 is provided with one or more helically extending ribs 22 and the hand of the rib or ribs is opposite to the direction of rotation. Thus, as seen in Figure 2, the direction of rotation for which the stirrer is intended is indicated by the arrow 2li, which is herein considered as a right hand or normal rotation of the device. The helical ribs 22 are left hand.

Conveniently, the ribs 22 may be provided by initially forming the shaft IS of square or other polygonal cross-section, after which the shaft is twisted so that the corners 2S of the shaft constitute helical ribs.

At the lower end of the shaft the blades 2l) are preferably constituted by a single generally iiat strip of material secured centrally to the bottom end of the shaft I8. This strip of material is bent and twisted in the zone indicated at 28 so as to provide flat straight blade portions which incline downwardly or away from the shaft I8 and which are also twisted about the longitudinal axis of said straight portions in such direction as to cause the paint to flow downwardly upon rotation of the blades.

The end portion of each blade 2E! is rounded as indicated at 3U. Moreover, the underside of each blade is provided with a flat surface 32 which is perpendicular to the axis of the shaft i 8 and which accordingly is adapted to engage the at bottom of a paint can. The flat surface 32 intersects the bottom surface 34 of the strip as well as the top surface 36 thereof. It will be appreciated that the arrangement described results in the formation of a sharp knife edge 27 where the flat surface 32 intersects the top surface 36 of the strip.

Also, the leading edge of the blade is provided with an inclined surface 38 which intersects the bottom surface 34 of the blade at 40.

This arrangement permits the tips of the blades to enter the bottom corners of the paint can so as to remove solid material therefrom. Moreover, the arrangement permits the tips of the blade to enter the paint can rotating in a manner to avoid splashing.

Conveniently, the strip of which the blades 20 are parts, may be provided with a threaded central opening at 42 and the eXtreme lower end of the shaft I8 may be threaded for engagement in the opening 42. Thus the blades may be readily removable from the shaft and if desired the blades may be furnished in sets of different size so that larger blades may be employed for larger cans of paint, while using the same size shaft. Alternatively, the shafts may be provided in sets of different lengths so that a stirrer comprising a shaft of the proper length and blade of the 3 proper size may be readily assembled together. In use, the blades force the paint downwardly against the bottom of the can whence it is forced to flow upwardly along the sides of the can, and

thence downwardly along the shaft to the zone of the blades, The helical rib provided on the shaft operates to facilitate downward flow of paint along the shaft, and in addition operates to throw excess liquid downwards into the can when the stirrer is moved up and down during mixing. Without this the paint tends to fly on by centrifugal action of the high speed rotation of the paint stirrer. This is particularly true when mixing full cans of paint Without first decanting the liquid.

In operation the pigment in the paint can is normally concentrated at the bottom Yand the blades operate in this area. Accordingly, the relatively violent action of the blades loosens the pigment and causes it to flow upwardly along the side of the can, whence it will flow inwardly and be mixed with the vehicle by the more gentle mining action of the helically twisted shaft.

I'he drawings and the foregoing specication constitute a description of the improved paint stirrer in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indin cated by the appended claim.

What I claim as my invention is:

In a paint stirrer for use in connection with an ordinary nat-bottom paint can, a rotatable shaft having helically disposed ribs thereon of a hand opposite to the direction of intended rotation of said shaft to force fluid to now downwardly along said shaft when the latter is thus rotated, and an agitator on said shaft adapted to force uid to ow downwardly upon rotation of said shaft in the direction aforesaid, said agitator comprising paddles secured to and extending radially outwardly from the lower end of said shaft, each of said paddles being twisted in a zone adjacent to said shaft to be inclined downwardli1 and rearwardly from the leading edge thereof, and each of said paddles being bent in said zone to extend downwardly from the lower end of said shaft and at a substantial angle thereto.

WILLIAM C. GRAY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 733,161 Comegys July 7, 1903 927,952 Cooke July 13, 1909 1,254,429 Parmelley Jan. 22, 1918 1,498,509 Arnold June 17, 1924 1,516,792 Ruggles Nov. 25, 1924 1,915,053 Dobyns June 20, 1933 2,108,482 Greene Feb. 15, 1938 2,137,432 Wilson et al. Nov. 22, 1938 2,203,672 Chester June 11, 1940 2,392,731 Fox Jan. 8, 1946 2,501,016 Woodman Mar. 21, 1950 2,515,713 Johnson et al July 18, 1950 FOREIGN PATENTS Number Country Date 278,152 Great Britain Oct. 6, 1927 

